Cutting pipe crimped fittings

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When cutting pipe to accept a elbow when using end feed fittings you could just push the pipe up to each other when you wanted to fit an elbow. And mark were the pipe meets, cut on that spot then fit an elbow. With crimp fittings they don't have as tight a radius. Is there anyway of marking this without holding a fitting up to the pipe to mark. Hope that makes sense if not I'll put some pictures up.
 
The fitting manufacturers will have data sheets which will give the required distances.
 
So you can make up as normally did with and end feed elbow then cut say 10mm back from this?
 
I usually can just cut were the pipes meet at a right angle to fit an elbow as shown by the pencil mark. However crimped fittings they have a larger radius. How do people usually mark these up to cut?
 

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It called the X dimension.

All copper, brass, plastic fittings use them. You are almost right, as far as squaring the pipes off against each other, most of the time that works fine as there's wiggle room or the other pipe is cut to suit as the setting out progresses. If you are setting out properly though to plans or diagrams you would then find that the pipe would grow a few mm each time and that can throw out a whole load of measurements further down the chain. If you look closely at the yorkie or the end fee - the swaged ends don't meet exactly at the corner right angle as the pipes do, they're a few mm out.

Pipework is usually measured centre to centre or centre to end - so you need to take the X measurement in to consideration to get the correct pipe lengths, that is exactly the same as press fit. The X dimension is from the end of the swaged section (pipe insertion distance) where the inserted pipe stops, to the centre line of oppposite leg. That X measurement is then subtracted from the required length.

It's part of the practical tasks that are included in level 2 plumbing (pipe skills) - all relative and applied in copper/plastic/waste fittings etc
 
Thanks so a crimped fittings seems to be mark were the pipes meet at a right angle. Then cut 10 mm further back
 
Draw a straight line down the centre of the fitting and extend that out onto the bend. Insert a piece of pipe into the fitting and mark the pipe at the end of the fitting, showing how far the pipe reaches into the fitting. Remove the pipe out the fitting and sit the pipe on top of it, lining up the mark on the pipe, to the end of the fitting, then measure the distance between the end of the pipe and the centre line mark on the fitting. That's the X dimension.

Subtract that measurement from the desired pipe length. Some are 10-12mm but on the press fit it'll be a fair bit more just looking at the larger radius, I'd guess.
 
By doing the centre line measurement, that gives you the pipe length for both ends. Else it would be from the inside of the bend?
 
I think I see what you mean but I think the OP is asking about where to mark for the cut if it isn't offered up to the pipe. I can only presume he has set lengths he needs to make and set out. It's not about the angle rather than the finished pipe lengths. The X dimension is how that's calculated and that's done using pipe centres or pipe centre to end measurements

This was similar to one of the exercises we had to do in Lvl 2 and had ensure it all ended up with those exact dimensions, that's done using the X dim.

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I think I see what you mean but I think the OP is asking about where to mark for the cut if it isn't offered up to the pipe. I can only presume he has set lengths he needs to make and set out. It's not about the angle rather than the finished pipe lengths. The X dimension is how that's calculated and that's done using pipe centres or pipe centre to end measurements

This was similar to one of the exercises we had to do in Lvl 2 and had ensure it all ended up with those exact dimensions, that's done using the X dim.

View attachment 350020

Maybe crossed wires but I was thinking when you have 2 fixed vertical pipes and need to know the horizontal length of pipe between them - allowing for internal radius of the fitting (x dimension)?
 
Yes - the X dimension (X-Dim) is used to get the exact length of pipe required - because pipes lengths are normally measure centre to centre or centre to end then the X-Dim is from the insertion length to the pipe centre and that's then subtracted, the radius doesn't really come into the measurement.
I only mentioned the radius because the radius of the press fit is larger /longer than the yorkie/end feed's therefore the actual X-Dim would be longer, so more to subtract.
 
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